Japanese honeysuckle
(Lonicera japonica)
An Alien Plant Report
Prepared by:
Forest Starr, Kim Martz and Lloyd Loope
United States Geological Survey Biological Resources Division
In cooperation with:
American Water Works Association Research Foundation
Maui County Board of Water Supply
March, 1999
Japanese honeysuckle
(Lonicera japonica)
What is Japanese honeysuckle? Why is it bad?
Japanese honeysuckle is a fast growing vine with glossy green leaves, and fragrant white
to yellow flowers. Japanese honeysuckle’s twining stems strangle vegetation and
anything else in its way.
In Koke’e on Kaua’i, Japanese honeysuckle is spreading and considered by some as
having the potential to be worse than Banana poka. On Maui, Japanese honeysuckle is
being used as a landscape plant. Please do not plant Japanese honeysuckle. If you see
this plant in the wild, pull it up and alert the HEAR project.
What should you do if you see this plant?
1. Call the Hawaii Ecosystems at Risk (HEAR) project at 572-4418.
2. Please do not plant this in your yard.
3. Pull out the vine, if possible. Otherwise, cut near the root of the plant, and treat with
an herbicide.
4. For more information or additional copies of this flyer, call 572-4418, or websurf to
www.hear.org.
You can help keep Maui no ka oi.
United States Geological Survey
Biological Resources Division
Japanese honeysuckle ( Lonicera japonica)
Maui County
Board of Water Supply
2
American Water Works Association
Research Foundation
Japanese honeysuckle
(Lonicera japonica)
Overview: Japanese honeysuckle is an invasive plant in Hawaii, New Zealand, and the
eastern part of North America. It has been widely used in horticulture and is known to
escape from gardens into adjacent lands, climbing and smothering other plants in its path.
It has been outlawed in both parts of the United States and New Zealand. In Hawaii,
even with its invasive history, it is currently sold and planted as ground cover.
Plants in Hawaii were originally thought not to produce fruit, yet viable seed producing
plants have been found on Maui in the course of this study. Japanese honeysuckle has
been observed spreading vegetatively from gardens into adjacent lands. Its ability to
produce viable seeds allows for long distance dispersal by birds or other animals which
would allow the plant to invade many more areas currently free of Japanese honeysuckle.
Japanese honeysuckle may be just beginning to occupy its potential range.
Potential public involvement: The invasive characteristics and problems associated
with Japanese honeysuckle have been well documented in the eastern United States and
New Zealand where it has been banned through noxious weed acts. Though, despite the
literature which warns of Japanese honeysuckle’s invasiveness, it is currently being
planted widely in Hawaii. This information may not be reaching the general public or it
does not seem like a real threat. Perhaps, only those acutely aware of alien species
problems realize the threat Japanese honeysuckle poses to Hawaii’s natural communities
and watersheds, even with the large amounts of information that has been written
documenting its invasiveness. Getting this information out to the general public, to
nursery owners, to landscapers, to children in schools, on the television, and on the radio
to raise public awareness about the potential harm of Japanese honeysuckle could
decrease its popularity and decrease the use of the plant in landscaping. Ultimately,
making it illegal to possess, as New Zealand and many parts of the United States have
done, would be the best way to minimize further spread.
Common name: Japanese honeysuckle, honekakala (Wagner et al. 1990), Chinese
honeysuckle (Williams and Timmins 1997).
Latin name: Lonicera japonica Thunb.
Taxonomy: In the Caprifoliaceae (honeysuckle) family, Lonicera is a genus of more
than 150 species of shrubs and woody twining climbers. Found in North America and
Eurasia south to northern Africa, the Philippines, and southwestern Malesia (Wagner et
al. 1990).
Description: This vigorous climber grows up to 30 ft (9 m), has glossy, dark green
leaves. Pairs of fragrant white flowers, ageing yellow or sometimes purple tinged
(Turner 1997).
Japanese honeysuckle ( Lonicera japonica)
3
Sprawling and twining lianas; young stems pubescent. Leaves ovate, elliptic, oblong, or
broadly lanceolate, blades 3-8 cm long, 1-3.5 cm wide, pubescent, becoming glabrate
above, entire or young lower leaves sometimes lobed. Flowers 2 in axillary cymes,
bracts 1-2 cm long, bracteoles suborbicular, ca. 1 mm long; corolla white, turning
yellowish or tinged pink, 2-lipped, 2-3 cm long. Berries bluish black, globose, 6-7 mm in
diameter (Wagner et al. 1990).
Noxious weed acts: Japanese honeysuckle is not listed on the United States Federal
Noxious Weed or Seed Lists. Japanese honeysuckle is not on the Hawaii Noxious Weed
List. Japanese honeysuckle is categorized as an exotic weed under the Illinois Exotic
Weed Control Act of 1987. As such, commercial sale in Illinois is prohibited (Nyboer
1990). In New Zealand, in 1995, Japanese honeysuckle was included on the Forest
Friendly list of plants unsuited for planting because of its known weediness (Craw 1994).
It is no longer permitted to be sold, propagated, distributed or commercially displayed on
the basis that it is now a Regional Surveillance Plant Pest within the Auckland Region
(Auckland Regional Council 1997).
Native range: Native to Asia (Wagner et al. 1990).
Range of invasion: Becoming a serious weed in areas such as eastern North America,
New Zealand, and Hawaii. Other areas where Japanese honeysuckle has invaded and is
now widespread include the southern parts of Australia through New South Wales and
Victoria, where it is regarded as a very serious threat to native vegetation (Carr et al.
1992), and wastelands in parts of Southern Chile (Williams and Timmins 1997).
In Hawaii, the first naturalized collection of Japanese honeysuckle was made in 1951
(Wagner et al. 1990). Today, Japanese honeysuckle is widespread in Hawaii (Cronk and
Fuller 1995). In Hawai’i, it is escaping cultivation in cool, mesic to wet areas in Koke’e
State Park, Kaua’i, on O’ahu, East Maui, and scattered localities on Hawai’i (Wagner et
al. 1990). On Maui, Japanese honeysuckle has been widely planted, though few
naturalized or wild populations exist far from original plantings. At most of these wild
populations, Japanese honeysuckle is moving vegetatively from intentional plantings into
adjacent lands. One wild population is located in a Eucalyptus grove with no signs that it
had been planted. It is not known whether this population has established through
secondary spread, by bird or other animal, from a nearby planting or whether is an old
house site and the Japanese honeysuckle is being persistent. Japanese honeysuckle may
just be beginning to establish in the wild on Maui.
In New Zealand, Japanese honeysuckle was being sold for horticulture use in 1872
(Esler 1988), and was first collected from the wild in 1926. Habitats invaded in New
Zealand include shrublands, forest margins, disturbed or secondary forest, wetland
margins, coastal areas and inshore islands, roadsides, farm hedges, wasteland, rough
pasture, modified lowland forest. More vigorous in deeper valley soils (Arulambalam
1998). Today, Japanese honeysuckle is widespread in the northern South Island but
uncommon in the south part of the island. On the North Island, it is currently listed as
widespread in almost all conservancies (Owen 1997). Typical areas invaded in New
Japanese honeysuckle ( Lonicera japonica)
4
Zealand include the hilly landscapes where there are untrimmed roadsides and unattended
land and associated areas of shrubbery, scrub, and forest remnants (Williams and
Timmins 1997). In these areas, Japanese honeysuckle is described as "patchy" and
displays a distributional pattern similar to other weedy plants whose primary dispersal
agent is humans, with secondary spread occurring by birds and other animals. After a
gradual secondary spread, plants become established then spread vegetatively, and so on
(Williams and Timmins 1997). Japanese honeysuckle still has much room to grow in
New Zealand. Making it illegal for humans to disperse the plant may retard its invasion
to areas still free of the weed.
In North America, Japanese honeysuckle was introduced in 1806. By the 1860's, it was
widely cultivated. It was first noted from the wild in 1882. The first documentation of
its spread was in 1904, almost one hundred years after its arrival (Andrews 1919;
Leatherman 1955). Today, Japanese honeysuckle is widespread throughout the eastern
United States. It is listed as a noxious weed in Illinois and as a pest plant in several other
eastern states.
Climate where invading: Cool, mesic to wet areas. Zones 4-10 (Turner 1997).
Japanese honeysuckle readily invades open natural communities, often by seed spread by
birds. An aggressive colonizer of successional fields, this vine also will invade mature
forest and open woodlands. Forests with either natural or unnatural openings are often
invaded by Japanese honeysuckle when birds drop seeds into these light gap areas. Deep
shading reduces the amount of invasion (Nyboer 1990). On Kauai, Japanese honeysuckle
is escaping and spreading in mesic to wet areas in Koke'e State Park, and near Volcano
and slopes of Hualalai, Hawai'i (Wagner et al. 1990).
On Maui, Japanese honeysuckle can be seen planted widely in a variety of conditions. It
has been successfully planted from sea level up to 4,200 ft (1,280 m), in dry and wet
areas, in shade and full sun, and in a variety of soils. Although, few naturalized or wild
populations can be found to date on Maui. Most naturalized populations have spread
vegetatively from plantings. Two naturalized populations are located below Haleakala
National Park, on Crater Road, Kula at 4,000 ft (1,219 m) and 4,200 ft (1,280 m)
elevation. The average annual rainfall in this area is about 40 in (Juvik and Juvik 1998).
One naturalized population is in full sun, possibly spread vegetatively from a nearby
planting. The soil is loamy and well drained. The other is in the full shade growing in a
grove of Eucalyptus, possibly spread by bird dispersal, as there are no signs of an
intentional planting, though this may be an old house site or abandoned water tank,
suggesting the plants could have been planted and are persistent. The soil is similar to
that of the first population mentioned. Another naturalized population is at the Waikapu
golf course, located at about 800 ft (244 m) elevation, spreading vegetatively into the
unmaintained surrounding scrub. Average annual rainfall at this site is about 30 in (Juvik
and Juvik 1998).
In North America, Japanese honeysuckle grows up to 5,905 ft (1,800 m) in both open and
shaded areas (Williams and Timmins 1997). Climatic limitations to growth in North
America include frosts in the northern region which causes death of shoots, low
Japanese honeysuckle ( Lonicera japonica)
5
precipitation in the western region, and lack of cold temperatures to break seed dormancy
in the south (Leatherman 1955). In New Zealand, plants grow from sea level up to 2,438
ft (743 m) (Williams and Timmins 1997). It is one of the few species of plants that are
tolerant of pollution from heavy metals and SO2 (Caiazza and Quinn 1980).
Value to humans: Useful as a ground cover or to quickly hide fences and posts. Some
varieties have been used in Chinese medicine since the Tang dynasty in 659 AD (Turner
1997). Japanese honeysuckle has been widely cultivated as an ornamental plant, as a road
bank stabilizer, and as food and shelter for wildlife (Handley 1945).
Problems: Japanese honeysuckle is considered a major pest due to its ability to
outcompete and shade out native vegetation (Cacek 1998). This aggressive vine
seriously alters or destroys the understory and herbaceous layers of the communities it
invades, including prairies, barrens, glades, flatwoods, savannas, floodplain and upland
forests. Japanese honeysuckle also may alter understory bird populations in forest
communities (Nyboer 1990). In New Zealand, Japanese honeysuckle infests forests and
climbs over shrublands or low canopy trees, especially on forest margins. Honeysuckle
may form a complete blanket over small trees and shrubs. It is becoming an increasingly
troublesome species of shrubland, forest margins, and open roadsides (Arulambalam
1998). Japanese honeysuckle is toxic if large quantities are eaten. The vines have
saponic and cyanogenic glycosoides. The fruits have carotenoids (Russell 1997). Effects
from eating large quantities of the fruit include vomiting, diarrhea, pupil dilation, cold
sweat, rapid heartbeat, respiratory failure, convulsion, and coma (Russell 1197).
Japanese honeysuckle has been known to escape from gardens to become a serious weed
elsewhere. In Hawaii, plants were previously thought to not bear fruit (Wagner et al.
1990). Wagner et al. (1990) suggest that if fertile strains develop, Japanese honeysuckle
could become an extremely serious weed. Recently, fruit has been observed on both
Oahu (Wagner et al. 1990) and on Maui. Viable fruit bearing plants allows dispersal by
birds and other animals into areas far from parent plants, in a polka dot pattern, whereas
non-fruit bearing plants can only spread vegetatively, in an amoebae like pattern. To
date, most naturalized populations observed have spread vegetatively from plantings.
Biology and ecology: Japanese honeysuckle climbs and drapes over native vegetation,
shading it out. It is capable of completely covering herbaceous and understory plants,
and climbing trees to the canopy. The semi-evergreen condition of this honeysuckle
allows for growth both prior to and after dormancy of other deciduous plants. The
prolific growth covers and smothers vegetation present including understory shrubs and
trees in forested communities. Vegetative runners are most prolific in the open sun and
will resprout where touching the soil, forming mats of new plants. This honeysuckle will
display little growth under moderate shade. In deep shade, runners develop but often die
back. Flowering and seed development are heaviest in open-sun areas. Seedling
establishment and growth is slow in the first 2 years of development of a new
honeysuckle colony (Nyboer 1990).
Japanese honeysuckle ( Lonicera japonica)
6
Associated animals: Insects known to feed on Japanese honeysuckle in North America
include indigenous hawk moths (Sphingidae), wax moths (Gelechiidae) and bumble bees
have been observed extracting pollen from flowers (Williams and Timmins 1997). A
wide range of birds are known to feed on fruit in North America from turkeys to small
passerines (Williams and Timmins 1997). Because of the high water content in the fruit,
the seeds pass quickly through birds (Handley 1945). Fruits are also eaten by mammals
such as deer and possums. Plants respond rapidly to herbivory pressures. However,
Japanese honeysuckle spread rapidly after forest reserves in New Zealand were fenced
and animals excluded (Williams and Timmins 1997).
Seed viability: According to Wagner et al. (1990), Japanese honeysuckle does not
usually produce fruit in Hawaii and if a fertile strain were to develop, it could become an
extremely serious weed. Recently, fruit bearing plants have been observed on Oahu
(Wagner et al. 1990). Japanese honeysuckle does indeed produce fruit on Maui as well.
Several locations of Japanese honeysuckle populations were monitored throughout the
year for phenology data and fruit production. The site descriptions are as follows.
Costco, located in Kahului, at sea level has several plantings surrounding the property
using Japanese honeysuckle as a ground cover, where it is spreading vegetatively into
unmaintained adjacent lots. Waikapu golf course, located in Waikapu, at about 800 ft
(244 m) on West Maui, also has several plantings escaping vegetatively into adjacent
unmaintained lands. Eddy Tam Park, located in Makawao, at 1,600 ft (488 m) elevation,
has Japanese honeysuckle planted as a ground cover on steep banks. Another site is a
residential planting located on Kekaulike Ave., Kula, at 3,700 ft (1,128 m) elevation
where Japanese honeysuckle is escaping into the adjacent gulch. The last two sites are
located on Crater Rd., Kula, one at 4,000 ft (1,219 m) and another just above at 4,200 ft
(1,280 m). At these two sites, the Japanese honeysuckle seemed slightly different in form
and fruit from other populations. We distinguish the two by the latter having a twining
habit, lighter green leaves, and glaucous, greenish-grey fruit. The different form may
prove to be a different species or variety. There are 180 different species of Lonicera and
several different cultivars of Lonicera japonica. Or, the differences may be attributed to
climatic factors. Further investigation is needed to be sure.
Fruit has been found at all sites checked to date. Fruit was first observed on December
15, 1998 on Kekaulike Avenue, Kula. Both immature and mature fruit was observed.
Immature fruit was bright green and glossy. Mature fruit was slightly larger, shiny, and
black. Fruit was observed at the Costco site on December 16, 1998. Most fruit found
were immature, small, shiny, and green. Fruit was abundant and found in clusters of
four. Fruit was observed at the 4,000 ft elevation site on December 19, 1998. Most fruit
at this site was immature. Both immature and ripe fruit was slightly different in color
than fruit observed at other sites, appearing a bluish-grey, green color, with a waxy white
film (glaucous). Fruit was found at the 4,200 ft Eucalyptus grove site on January 5, 1999.
Fruit appeared similar to that found at the 4,000 ft site. Fruit was found at the Eddy Tam
site also on January 5, 1999. Mature fruit was black, and glossy, similar to typical fruit
found. Once fruit was observed on Maui, the next question to answer was whether or not
the seeds in the fruit were viable. Fruit was collected from the 4,000 ft site on January 5,
Japanese honeysuckle ( Lonicera japonica)
7
1999 and from the Kekaulike Ave. site on December 15, 1998 for further comparisons
and germination tests.
Site descriptions:
Kekaulike Ave.: Japanese honeysuckle appeared planted on a bank bordering Kekaulike
Ave. Plants were naturalizing into Keahuaiwi gulch, by Pulehu bridge, along with other
weedy horticulture plants such as Mexican daisy (Erigeron karvinskianus), cape ivy
(Senecio mikanioides), Vinca (Vinca spp.), Cotoneaster (Cotoneaster spp.), and butterfly
bush (Buddleia madagascariensis). This population is representative of common
Japanese honeysuckle.
4,000 ft: Japanese honeysuckle is located on the side of the road, climbing up a
telephone pole wire. It may be spreading from a planting, however, this in inconclusive.
It is mixed with other weedy plants such as hill raspberry (Rubus niveus), waddle (Acacia
mearnsii), olive (Olea europaea cuspidata), and cotoneaster (Cotoneaster spp.). This
form appears different than common Japanese honeysuckle.
Fruit descriptions:
Kekaulike Ave.: Ripe fruits were shiny black, measuring from 5 mm to 10 mm in
diameter. 46 fruits were collected. One fruit had a sizeable hole with seed aril and seeds
still intact. Pulp from fruit was greenish and stained paper on which it was a greenish
color. Another fruit found did not have any seeds or pulp left as if eaten out by some
thing. It is not known what may have eaten the seeds and pulp and left the skin of the
fruit.
4,000 ft: The fruit has a thing skin, like that of a grape. It starts out green and turns black
to purple as the fruit ripens. There is a sort of white haze on the surface or skin. The
pulp is green and the seeds are green to brown. The fruit looks smaller than other
Japanese honeysuckle fruit we have observed at Kula, Kahului, and Makawao. We had
always thought this Japanese honeysuckle looked different, with its viney habit, leaves
that look a little lighter in color, more fruit per axil, and fruit are smaller with a white
sheen. There are also less seeds per fruit. The following table displays these differences
in fruit characteristics.
Site
Kekaulike Ave.
4,000 ft
Ave. diameter of
fruit (mm)
5.78
4.79
Ave. # seeds per
fruit
5.3
1.56
Ave. diameter of
seed (mm)
4.38
3.075
Germination: After seeds were removed from the fruit, 50 random seeds from each site
were placed in petri dishes, 25 seeds per petri dish, on moist paper towels. Seeds were
kept moist by periodically adding bottled water to the petri dishes. Seeds were monitored
for germination. Germination was defined as sending out a root radicle. Germination
percentages may increase further over time, however, for the purposes of this report, the
experiment ran for 10 weeks.
Japanese honeysuckle ( Lonicera japonica)
8
Out of the 50 seeds from the Kekaulike site, one germinated, or 2 %, after 10 weeks. Out
of the 50 seeds from the 4,000 ft site, 27 germinated, about 54 %, after 10 weeks. This
raises a few questions. Is the 4,000 ft site population a different strain that is more viable
and more likely to invade in Hawaii? Or, are there climatic factors such as high elevation
and colder temperatures, which contribute to greater seed viability at this site? Further
investigation is needed to make these conclusions.
Japanese honeysuckle was first found naturalizing in Hawaii in 1951 (Wagner et al.
1990). It is a serious weed in eastern North America and New Zealand where it is now
illegal to sell, propagate, distribute, or commercially display it. On Maui, Japanese
honeysuckle is currently being planted widely in many areas where it has spread
vegetatively into adjacent lands. Viable fruit producing plants will allow long distance
dispersal to lands currently free of Japanese honeysuckle. Public awareness and further
documentation of its invasive characteristics are needed in order to decrease further
plantings and spread of Japanese honeysuckle.
Physical control:
Cutting: Vines may be chopped just above ground level. Cutting is repeated every two
weeks to deplete nutrient reserves in the roots and prevent resumption of photosynthesis.
Cutting does not affect roots, which will continue to grow until their energy and nutrient
supplies are depleted (Cacek 1998). Mowing limits the length of Japanese honeysuckle
vines, but will increase the number of stems produced (Nyboer 1990).
Flaming: By placing a kerosene torch over leaves on the same schedule as cutting,
foliage is wilted and nutrient supplies in the roots are depleted. As with cutting, flaming
will not affect roots.
Burning: Although few quantitative studies occur in the literature, Barden and Matthews
(1980) recommend controlled burning. Two annual burns in an experimental plot reduced
honeysuckle crown volume by 80%. Ground cover was reduced by 35%. Fires killed
most aboveground vines, but ground cover was maintained by re- sprouting roots.
Burning may be combined with previous flaming, which wilts and dries leaves, providing
fuel for the burn (Cacek 1998).
Grubbing: Consists of mechanical removal and destruction of the entire plant, including
the root. If all root tissue is removed, no regrowth can occur, and repetition is not
necessary. Grubbing is labor intensive and may be locally destructive. Grubbing is most
effective from fruiting to winter and early spring when plant reserves are lowest.
Grazing: Controlled grazing by goats may serve to reduce honeysuckle crown and
ground cover densities, but as with controlled burning, re-sprouting roots will regenerate
unless nutrient reserves are depleted by continuous grazing pressure.
Regardless of the control method used, care must be taken to prevent re- invasion from
nearby areas, or by seeds transported by birds or other wildlife. Planting the area with
fast-growing native vegetation or grasses may prevent recolonization (Cacek 1998).
Japanese honeysuckle ( Lonicera japonica)
9
Chemical control: Mclemore (1981) reports that an acceptable level of control (70%)
was reached during a two-year experimental program which used 2 lb/acre of glyphosate
in the first year and 6 lb/acre in the second year. Japanese honeysuckle is an evergreen, so
it can be treated in the dormant season with less damage to non-target species (Cacek
1998). In New Zealand, they cut base of stem and paint with stump paint herbicide mix.
Alternatively spray with Escort + Pulse or Tordon Brushkiller herbicide. Cut large vines
at head height and spray below this point. Roundup has been found to be ineffective
(Arulambalam 1998). Spray infestations on open ground with Escort. To save trees
which are growing under or through honeysuckle, cut and paint stems or use Tordon
Granules (Arulambalam 1998). In temperate areas, because Japanese honeysuckle is
semi-evergreen, it will continue to photosynthesize after surrounding deciduous
vegetation is dormant. This condition allows managers to detect the amount of
infestation, and allows for treatment of the infestation with herbicides without damage to
the dormant vegetation (Nyboer 1990).
Glyphosate herbicide (trade name Roundup) is the recommended treatment for this
honeysuckle. A 1.5-2% solution (2-2.6 oz Roundup/gallon water) applied as a spray to
the foliage will effectively eradicate Japanese honeysuckle. Although glyphosate is
effective when used during the growing season, use at this time is not recommended in
natural areas because of the potential harm to nontarget plants (Arulambalam 1998).
Crossbow, a formulation of triclopyr and 2,4-D, is also a very effective herbicide that
controls Japanese honeysuckle. Crossbow should be mixed and applied as a foliar spray.
Herbicides that have given poor control results or that are more persistent in the
environment than other types are picloram, annitrole, aminotriazole, atrazine, dicamba &
2,4-D, 2,4_D, DPX 5648, fenac, fenuron, simazine & triclopyr.
Biological control: No natural enemies are reported for this species (Cacek 1998).
Management recommendations: Japanese honeysuckle has a extensive history as an
invasive species, yet is widely planted on Maui in schools, parks and housing complexes
and can be bought in most garden shops. Recently, viable fruit have been found, and it
has been seen spreading into wild lands. Perhaps the best strategy for Japanese
honeysuckle is to stop selling it and control infestations adjacent to wild lands. Raising
public awareness may help to prevent future plantings, and putting it on the State
Noxious Weed List would provide legal authority for those looking to control the spread
of Japanese honeysuckle.
Key contacts:
Maui:
USGS/BRD Haleakala Field Station
PO Box 369
Makawao, HI 96768
(808) 572-4472
Kaua’i:
Japanese honeysuckle ( Lonicera japonica)
10
Guy Nagai
Hawai’i State Department of Agriculture
4398A Pualoke St.
Lihue, HI 96766-1673
(808) 274-3069
REFERENCES & BIBLIOGRAPHY:
Andrews, E.F. 1919. The Japanese honeysuckle in the eastern United States. Torreya
19: 37-43.
Aukland Regional Council. 1997. Pest Facts #43, Japanese honeysuckle, Lonicera
japonica. Auckland.
Arulambalam, R. 1998. Weeds of New Zealand.
http://www.boprc.govt.nz/www/green/WEED63.HTM.
Barden, L. S., and J. F. Matthews. 1980. Change in abundance of honeysuckle
(Lonicera japonica) and other ground flora after prescribed burning of a piedmont pine
forest. Castanea 45:257-260.
Cacek, T. 1998. The National Park Service Integrated Pest Management Manual.
http://www.colostate.edu/Depts/IPMnatparks/exweeds2.html.
Caiazza, N.A., and J.A. Quinn. 1980. Leaf morphology in Arenaria patula and Lonicera
japonica along a pollution gradient. Bulletin of the Torrey Botanical Club 107: 9-18.
Carr, G.W., J.V. Yugovic, and K.E. Robinson. 1992. Environmental weed invasions in
Victoria. Department of Conservation and Environment and Ecological Horticultural
Pty. Ltd., Melbourne. 78 p.
Craw, J. 1994. Keeping our gardens forest friendly. Forest and Bird 271: 8-12.
Cronk, Q.C., and J. Fuller. 1995. Plant Invaders. Chapman Hall, London. 241 p.
Esler, A.E. 1988. Naturalised plants in urban Auckland: a series of articles from the
New Zealand Journal of botany. DSIR Publishing, Wellington. 618 p.
Handley, C.O. 1945. Japanese honeysuckle in wildlife management. Journal of Wildlife
Management 9: 261-264.
Juvik S.P and J.O. Juvik. 1998. Atlas of Hawai'i. Third edition. Department of
Geography, University of Hawai'i press.
Leatherman, A.D. 1955. Ecological life-history of Lonicera japonica Thunb.
Unpublished PhD thesis, University of Tennessee (Library of Congress Card No. Mic.
Japanese honeysuckle ( Lonicera japonica)
11
55-772). 97 p. University Microfilms, Ann Arbor, Michigan (Dissertation Abstracts 15
(11): 1987, Publication No. 15,076).
McLemore, B.F. 1982. Comparison of herbicides for controlling hardwoods in pine
stands. Proceedings of the 35th annual meeting of the Southern Weed Science Society
1982. 195-199.
Nyboer, R. 1990. Vegetation Management Guideline Japanese Honeysuckle.
http://www.inhs.uiuc.edu/edu/VGM/jhnysckl.html.
Owen, S.J. 1997. Ecological weeds on conservation land in New Zealand: A database.
Department of Conservation, Wellington.
Russell, A. B. 1997. Poisonous Plants of North Carolina.
http://russell4.hort.ncsu.edu/poison/Lonicja.htm.
Turner, R. J. Jr., E. Wasson. 1997. Botanica. Random House Australia. NSW
Australia. 1007 pp.
University of Hawaii, Botany Department Web Page. Alien plants of Hawaii. Lonicera
japonica. http://www.botany.hawaii.edu/faculty/cw_smith/lon_jap.htm.
Wagner, W.H., D.R. Herbst, S.H. Sohmer. 1990. Manual of the Flowering Plants of
Hawai’i. University of Hawai’i press, Honolulu, Hawai’i.
Williams, P.A., and S.M. Timmins. 1997. Biology and ecology of Japanese honeysuckle
(Lonicera japonica) and its impacts in New Zealand. Landcare Research Contract
Report: LC 9798/013. D
Japanese honeysuckle ( Lonicera japonica)
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Japanese honeysuckle fruit and flower
Japanese honeysuckle rooting at the nodes - Kula, Maui
Japanese honeysuckle ( Lonicera japonica)
13
Typical use of Japanese honeysuckle in landscaping - Eddie Tam Park, Makawao, Maui
A stand of Japanese honeysuckle escaping into Eucalyptus grove - Kula, Maui
Japanese honeysuckle ( Lonicera japonica)
14
Japanese honeysuckle fruit used in germination trials.
Counting Japanese honeysuckle seeds and preparing them for germination trials
Japanese honeysuckle ( Lonicera japonica)
15
Known global distribution of Japanese honeysuckle
Known distribution of Japanese honeysuckle in the state of Hawaii, USA
Japanese honeysuckle ( Lonicera japonica)
16
Known distribution of Japanese honeysuckle on the island of Maui, state of Hawai'i
Japanese honeysuckle ( Lonicera japonica)
17